Research Center for Analytical Sciences, Department of Chemistry, College of Sciences, Northeastern University, Box 332, Shenyang 110819, China.
Nanoscale. 2020 Mar 28;12(12):6852-6860. doi: 10.1039/c9nr10982j. Epub 2020 Mar 18.
Regulating the fluorescence of carbon dots (CDs) is important but highly challenging. Here, carbon dots with tunable dual emissions were facilely fabricated via modulating the polymerization and carbonization processes of o-phenylenediamine (OPD) with lysine (Lys) as the co-precursor and modulator, respectively. The self-polymerization/carbonization of the OPD molecules contributed to the blue/green emission of the OPD-derived CDs. The introduction of Lys in the CD fabrication process efficiently suppressed the carbonization of the OPD polymer chains and enhanced the self-polymerization of the OPD molecules. Meanwhile, the formed OPD-Lys co-polymer chains endowed the final CD product with a new green emission center. The dual-emissive CDs were distinctly sensitive to polarity fluctuations, providing a ratiometric fluorescence response towards solution polarity. Due to their specific distribution in the endoplasmic reticulum (ER), the as-prepared dual-emissive CDs successfully distinguished the polarity variations in ER under stress, which offers a new approach for the early diagnosis of cell injury.
调控碳点（CDs）的荧光性质非常重要，但极具挑战性。在这里，我们通过赖氨酸（Lys）分别作为共前体和调节剂来调节邻苯二胺（OPD）的聚合和碳化过程，从而简便地制备出具有可调谐双发射的碳点。OPD 分子的自聚合/碳化有助于 OPD 衍生的 CDs 的蓝/绿光发射。在 CD 制备过程中引入 Lys 可有效抑制 OPD 聚合物链的碳化，并增强 OPD 分子的自聚合。同时，形成的 OPD-Lys 共聚物链为最终的 CD 产物赋予了新的绿色发射中心。双发射 CDs 对极性波动具有明显的敏感性，可提供对溶液极性的比色荧光响应。由于它们在细胞质内质网（ER）中的特定分布，所制备的双发射 CDs 成功地区分了应激下 ER 中的极性变化，为细胞损伤的早期诊断提供了一种新方法。
